Various fuel systems directed to increased efficiency for internal combustion engines exist in the prior art. For example, U.S. Pat. No. 3,872,191, to Walcker, includes a fuel processing unit with a helical wound heat exchange tubing and surrounding fine wire mesh screen. Liquid fuel flows downward by gravity over the hot wire mesh screen heated by the coiled tubing to vaporize the fuel. The vapor fuel is mixed with air and sent to the engine intake manifold. Since the fuel is gravity fed with resultant limited vapor conversion, Walcker may be impractical.
U.S. Pat. No. 4,023,538 to Harpman, describes a device which simultaneously vaporizes gasoline and water in a multi-chambered heated pressure vessel with built in regulators for controlling pressure and volume. This device also lacks control of vapor production with resultant limited vapor production, such that operation is limited to speeds near 35 m.p.h.
The hot fuel gas generator disclosed in U.S. Pat. No. 4,050,419, also to Harpman, simultaneously vaporizes gasoline and water, and includes a metering valve for adding air to the gaseous fuel. Vapor conversion from this device is limited, because the vaporizing means is an electronic resistance heating element. This device may also be impractical due to uncontrolled mixing of air and fuel vapor and inefficient delivery of the vapor fuel through a passageway of a tube and a metering valve.
U.S. Pat. No. 4,366,797, to Jackson and Arndt, includes a fuming tank for providing a fumed fuel-air mixture to the carburetor. The fumed fuel is prepared by passing a vortex of air through a diffusing member and across the surface of the liquid fuel.
U.S. Pat. No. 4,368,712, also to Jackson and Arndt, discloses an electronic monitoring and control system to monitor combustion of the vaporized fuel and air mixture, for increased responsiveness to the engine's demand for fuel.
U.S. Pat. No. 4,397,286, also to Jackson and Arndt, further discloses a vaporous gasoline aspiration system and fuming tank, wherein some vanes of the dispersing members are curved in opposite directions.
U.S. Pat. No. 4,469,075 to Jackson, Arndt and Maynard, provides electronic means co-acting with the engine and fuel system, including monitoring of the manifold vacuum, oxygen content of exhaust gases, engine coolant temperatures, engine throttle signal, output fuel signal and output air signal, for responsiveness to the engine's operative load and for controlling the fuel to air intake ratio.
However, none of the above prior art teaches the efficient, direct heating of liquid fuel by surrounding the vapor line with hot gases from the engine exhaust manifold, and employing those extremely hot gases as a means for vaporizing the fuel. The vaporizing mechanisms of the prior art do not produce vapor fuel rapidly enough to accommodate the widely divergent fuel requirements of state-of-the-art engines. Generally, the volume of vapor fuel created in prior art devices is insufficient; the means for mixing air and vapor fuel is uncontrolled; and the means for delivery of the vapor fuel to the engine is inefficient.